I'm required to have double locking biners for work, after figuring out how to open the gate one handed no matter what orientation the biner is in, especially with gloves on (also required in my line of work), these are by far the best biner I've used. Like them so much that I bought a bunch of them for my recreational climbing.

I've got a co-worker that liked the ball-locks, I don't care for them, much tougher to operate with gloves on. After he saw how much easier the Triacs were to operate, he bought a bunch of those to replace his ball locks.

As for recreational climbing, lots of folks swear by screw locks, saying the Triac style gate will get dirty and start to hang up...to that I say they are not taking proper care of their climbing gear to start with if it gets that dirty. To each their own, people with smaller hands might have more difficulty operating the Triac, but my 10 yo Daughter has smaller hands than most with that complaint; she has no problem using them with one hand.

Of course they are a bit more expensive, but you get what you pay for.

I have the regular screw lock version and it's really nice. The screw lock is crazy smooth and the biner is nice and big. Although any future lockers I get will be pear shaped ones.

Great locker. You may have to clean it ocassionall with once you've master the ball it is very quick to connect. It works great for ice and alpine.

Got it as a gift, not sure if I'd pay for one myself. Seems really pricey for a simple D. I use it on my PAS, the snag free nose is nice for this, it's large enough to clip the extra loops in there without making a huge mess. Also I only have one, so I can tell by feel which biner I need to unclip to get my tether free. Great gate action, petzl makes good stuff. This thing is just way too expensive to justify itself. 3-4 stars, but I didnt pay for it, so it gets a 4.

The ball-lock is strange and like others I would get the screw-lock next time. I like the size and shape of it though.